In the post genomic era we are in the position to investigate the epigenomics of psychiatric illnesses in a systematic genome-wide fashion. Advances in experimental and computational technology have revolutionized the field of epigenetics. The sequencing and annotation of the human genome and other model organisms to date has provided a rich resource to study the form and function of genomic methylation in context of other functional features of the genome. However, the existing genome projects have largely ignored genomic methylation patterns, and while it is known that even partial demethylation alters the stability of the genome and the regulated expression of genes, little is known of the organization of genomic methylation patterns. The aim of the proposed research plan is the identification and characterization of the epigenetic profile of MDD in selected brain regions from MDD subjects and to identify differences in epigenetic patterns relative to controls. In this way we aim to discover genomic elements that may be used as an added component in disease studies, as they may be risk factors for such multifactorial diseases, like MDD.